<!--
 * @Descripttion: 局部水印组件
 * @version: 1.1
 * @Author: sakuya
 * @Date: 2021年12月18日12:16:16
 * @LastEditors: Xujianchen
 * @LastEditTime: 2023-03-18 13:14:19
-->

<template>
	<div ref="scWaterMark" class="sc-water-mark">
		<slot></slot>
	</div>
</template>

<script>
export default {
	props: {
		text: { type: String, required: true, default: '' },
		subtext: { type: String, default: '' },
		color: { type: String, default: 'rgba(128,128,128,0.2)' }
	},
	data() {
		return {}
	},
	mounted() {
		this.create()
	},
	methods: {
		create() {
			this.clear()
			//创建画板
			var canvas = document.createElement('canvas')
			canvas.width = 150
			canvas.height = 150
			canvas.style.display = 'none'
			//绘制文字
			var text = canvas.getContext('2d')
			text.rotate((-45 * Math.PI) / 180)
			text.translate(-75, 25)
			text.fillStyle = this.color
			text.font = 'bold 20px SimHei'
			text.textAlign = 'center'
			text.fillText(this.text, canvas.width / 2, canvas.height / 2)
			text.font = '14px Microsoft YaHei'
			text.fillText(this.subtext, canvas.width / 2, canvas.height / 2 + 20)
			//创建水印容器
			var watermark = document.createElement('div')
			watermark.setAttribute('class', 'watermark')
			const styleStr = `position:absolute;top:0;left:0;right:0;bottom:0;z-index:99;pointer-events:none;background-repeat:repeat;background-image:url('${canvas.toDataURL(
				'image/png'
			)}');`
			watermark.setAttribute('style', styleStr)
			this.$refs.scWaterMark.appendChild(watermark)
		},
		clear() {
			var wmDom = this.$refs.scWaterMark.querySelector('.watermark')
			wmDom && wmDom.remove()
		}
	}
}
</script>

<style scoped>
.sc-water-mark {
	position: relative;
	display: inherit;
	width: 100%;
	height: 100%;
}
</style>
